Internal-combustion engine



15, I929. 1,699,228 7 J. H. DE GRAER INTERNAL COMBUSTION Enema Filed April 21, 1925 4 Shoots-Sheet 1 Vani Jan. 15, 1929.

J. H. DE GRAER INTERNAL COMBUSTION ENGINE 4 sums-sheet 2 Filed April 21, 1925 I V I h In ve nCa J. H. DE GRAER Im'snnn. couaus'nou nuemg' Jan; 15, 1929;

4 Shuts-Sheet Filed April 21, 1925' Y J. H. DE GRAER INTERNAL COMBUSTION ENGINE Filed April 21, 1925' 4 Shasta-$11 9; 4

e/ i I. a! I] an I a N. k .50 ea Patented Jan. 15.1929.

JUL-ES HECTOR DE GRAER, F BRUSSELS, BELGIUM.

INTERNAL-COMBUSTION ENGINE.

Application filed April 21, 1925, Serial No. 24,717, and in Belgium April 24, 1924.

My invention relates to internal comhus tion engines of the four cycle type in which a suitable fuel is spontaneously ignited under a high compression.

One object of my invention is to secure an engine of this type of a very compact construction adapted to develop a given power under a reduced volume and very small weight and to operate without the use of any ignitin or sparking device.

AIlOlilGl object of my invention consists in providing means whereby the compression may be greatly increased, thus improving the efiicienoy of an engine of given propon tions.

With these and other objects in view, as will more fully hereinafter appear, my inven tion essentially consists in special arrange ments and combinations of parts as will be hereinafter full described and pointed out in the appende claims.

Referring to the annexed drawings, which show as an example one embodiment of my invention:

Fig. 1 is a vertical section through the axis of the cylinders of an engine constructed according to my invention and comprising two sets of driving cylinders cooperating with two starting cylinders, the said section being taken on line l--l in Fig. 4.

Fig. 2 is a, vertical transverse section taken on line 22 in Fig. 4.

Fig. 3 is a similar vertical transverse section taken on line 33 in Fig. 4.

Fig. 4 is a top view showing diagrammatically the arrangement of the cylinders and distributing valves.

Fig. 5 is a vertical transverse section taken on line 5-5 of Fig. 4.

The engine shown comprises a boxor crank-casing 1 in which a crankshaft 2 is rotated by connecting rods 3 connected to pistons 4 having a reciprocating movement in cylinders which are formed in a single block 5. In the example shown, it has been supposed that the engine comprises two groups of twin cylinders between which two starting cylinders are arranged. The driving cylinders of each group are indicated by 6 and 7, the cylinders 6 being the cylinders in which a suitable fuel such as hydrogen after having been introduced under a suitable pressure is highly compressed and the cylinders 7 being the cylinders used for the compression of the air or oxygen necessary for the combustion of the fuel. As

shown in the drawings the pistons acting in the said cylinders have a relatively great length corresponding substantiall to the length of the stroke so as to be a le to receive a great number of packing rings 8 in order to prevent any leakage, notwithstanding the high compression at which the engine operated.

Between the two groups or pairs of twincylinders 6 and 7 are arranged two starting cylinders 9 in each of which a piston 10 reciprocates. These starting cylinders are connected by ducts 11 which are shown in dotted lines in Fig. 4, and which are provided in the head of the block 5, with chambers 1213 containing respectively the inlet and outlet valves (in this case piston valves) for the gas under pressure, which is used for the starting of the engine.

The head of the block 5 is provided in the axial plane of each group of cylinders 6-7 with two passages 14 adapted to be put in communication with each other by the movement of a piston valve 15 which is reciprocated in a corresponding chamber of the cylinder-block. Each cylinder 6 further communicates laterally by ducts 16-17 with chambers 19-20 which are closed by covers.

21; within the said chambers are arranged pistonvalves 22 (Figs. 4 and 5) for the inlet of a combustible gas and the escapeof the burnt gases. The cylinders 7 are similarly connected by ducts 2324 (Figs. 2 and 4) with chambers 25-26, similar to the chambers 19-20 and within which are arranged piston valves 27 controlling the inlet of the inning gas on one side and the escape of i the products of combustion of the 7 on the other side. a

The chambers 19 corresponding to the cylinders 6 are in communication through suitable connections 28 (Figsn l and 5) with the feed-pipe 28 for the combustible gas and through passages 29 with a collector 30 (Fig. 4) for the burnt gases.

The chambers 25 corresponding to thejcylinders 7 are similarly connected at 31 with the feed pipe Fig. 5, for the burning gas or in the present instance with atmospheric air whilst the chambers 26 are.connected with the general collector 30 already referred to (Figs. 2 and 4).

The several distributing valves 22-27 (in the case shown, the pistonvalves) may be acted upon by any suitable means. In the example shown a distributing shaft 32 (Fig.

cylinders 2) is provided on each side of the longitudi' nal axis of the engine, the said shaft being driven from the crank-shaft 2 by toothed wheels 33343536.

One of the shafts 32 acts by cams 37 on all the piston-valves which are used for the inlet and which are acted upon by springs 38 holding their rods 39 in contact by rollers 40 (Fig. 2) with the corresponding cams. The second shaft 32 acts similarly bycains 41 on all the piston-valves which are used for the escape of the burnt gases and by cams 42 (Fig. 3) on the piston-valves 15 through which the communication is established between the passages 14 connecting the cylinders 6-7 of a same group or pair of twin cylinders. To this end, the piston-valves 15 are acted upon by oscillating levers 44 pivotally mounted at 45 on the head of the cylinder block and which are acted upon by the rods 43 which are lifted by the cams 42.

, The method of operation of the engine is as follows: I

If it is supposed that the piston-valves 22 located in the chambers 19 and the pistonvalves 27 located in the chambers 25 have established the required communications respectively between the cylinders 6 and 7 and the connections 28 and 31 at the moment that the pistons 4 of the cylinders 6 and 7 are at the upper end of their strokes (after an escape period) air will be sucked in the cylinders 7 through the connections 31 and combustible gas, hydrogen under a certain pressure for instance, will be caused to enter into the cylinders 6 through the connection 28 (Fig. 4) during the following downward stroke of pistons 4 in the said cylinders. The cylinders 6 and 7 will consequently be filled with a volume of gas and with a volume of air respectively, corresponding to a full charge of the cylinders. During the following ascending stroke of the pistons in both cylinders 6, and 7 of a same group or pair of cylinders, the air and the gas (hydrogen for instance) (after the passages controlled by the piston valves have been closed) will be compressed in the cylinders to a very high pressure say for instance to about 40 atmospheres which pressure will be attained, when the pistons will have reached the upper end of their stroke.

At this moment, the piston-valves 15 will be acted upon by the oscillating levers 44 and will establish the communication between the passages 14 (position of Fig. 1)

. thus causing the air and gas, separately compressed, to mix in the compression chambers at the upper end of the cylinders. The mixture thus formed will ignite spontaneously owing to the heat resulting from the high compression and will burn simultaneously in the two cylinders 6 and 7 of the same group, thus expanding in the said cylinders and acting on the pistons which will perform their working stroke. This stroke being completed, the piston-valves 15 are again displaced, the piston-valves 27 in the chambers 26 open the passages 24 and the burnt gases, during the subsequent ascending stroke of the pistons, are expelled through the connections 29 into the collector 30. The engine consequently acts on the four-cycle principle, the combustible gas and the burning gas being compressed independently in the corresponding cylinders before the mixture resulting from the opening of piston-valves 15 can exert its driving action simultane' ously in both cylinders of a same group or pair of cylinders.

An engine of this type having no igniting or sparking device, the first driving stroke at the moment of starting must obviously be produced by auxiliary starting means. In the example shown, these auxiliary starting means consist of two starting cylinders 9 arranged between the two pairs or groups of working cylinders 67. The starting is easily obtained by keying the cranks of the starting piston 10 in a suitable position relatively to the cranks of pistons 4 in such a manner that when the said pistons rest in a balanced position, one of the starting pistons 10 will be at the end of its ascending stroke. The inlet piston valve, located in the cha1nher 12 corresponding to the piston which rests in its starting position uncovers at this moment the passage 11 leading to the starting cylinder in such a manner that it is only necessary to open a cock to produce an inlet of gas under'pressure in the cylinder 9 to secure the starting and to produce the first suction and subsequently the first compression in both cylinders 6-7 of a same group. To thisend the chambers 12 (Fig. 4) containing the piston-valves cooperating with the starting cylinder 9 communicate through passages 45 with a box 46 connected at 47 to a feeding pipe for the gas under pressure. The chambers 13 containing the piston valves controlling the escape of the gas after it has exerted its starting action in the starting cylinders 9, are connected directly through passages 48 (Fig. 4) to the collector If necessary the starting may be facilitated as usually by lifting manually the escape piston valves of the cylinders 6-7 so as to v reduce the resistance due to the compression.

In the example shown, the engine constructed as described is supposed to be operated by air and hydrogen, for this reason the cylinders 7 whichare used for the compression of the air liavea larger diameter than the cylinder 6 which areused for the combustible gas.

In practice the diameter of the cylinders 7 will vary according to the nature of the burning gas and the power of the engine.

In case the burning gas should be oxygen,

IOU

the diameter of the cylinders 7 could obviously be reduced and eventually be the same as the diamenter of the cylinders 6. As the engine is intended to be operated with a full charge of combustible gas to secure the re quired compression for the spontaneous ignition of the mixture, the variationof power of the engine will preferably be obtainedby varying the number of groups or pairs of the Working cylinders or by varying the initial pressure of the combustible gas before its admission to the cylinders.

I am aware that it has already been pro posed in internal combustion engines to make use of a mixture of gas and air compressed in a working cylinder and of a volume of air compressed separately in another cylinder, the explosive mixture and the air being then mixed together at the momentof sparking by the opening of a passage between both cylinders. It is also known to feed combustion engines with hydrogen as combustible gas and with oxygen as burning ,gas, generally speaking engines of this kind have been fitted with a special igniting device. In the present instance, the engine constructed according to my invention is distinguished from the constructions already known by the fact that it works without any auxiliary igniting device, with a combustible gas which is fed to the cylinders under a given'pressure and which is then compressed to a very high pressure independently of the burning gas, in such a manner that the mixture takes place only at the moment that the desired compression is attained, which prevents any dangerous and pre-ignition of the mixture.

What I claim is:

1. In an internal combustion engine, pairs of working cylinders, each pair comprising a cylinder for the com ression of a combustible gas and a cylindizr for the compression of a burning gas, pistons acting in the said cylinders, a crank shaft, connecting rods between the said crankshaft and the pistons, a separate supply of a combustible gas to one cylinder of each pair of cylinders and a separate supply of a burning gas to the second cylinder of each pair of cylinders, means for automatically establishing a communication between both cylinders of each pair when the corresponding pistons are at the end of their compression stroke, whereby a mixture is formed which ignites spontaneously in both cylinders of each pair, exhaust valves cooperating with each cylinder of the several pairs of cylinders for the escape of the burnt gases and starting cylinders arranged between the several pairs of working cylinders.

2. In an internal combustion engine, pairs of working cylinders, each pair comprising a cylinder for the compression of a combustible gas and a cylinder for the compres sionof a burning gas, istons acting in the said cylinders, a crank-shaft, connecting rods between the said crank-shaft, and the pistons, a separate supply of a combustible gas under pressure to one cylinder of each pair of cylinders and a separate supply of a burning gas to the second cylinder of each pair of cylinders, a passage between both cylinders of each pair, a valve arranged in the said passage, means for actuating said valve, whereby a communication is established between both cylinders of each pair when the corresponding pistons are at the end of their compression stroke and a combustible gas mixture is formed which ignites spontaneously in both cylinders of each pair under the action of the compression heat, exhaust valves cooperating with each cylinder of the several pairs of cylinders for the escape of the burnt gases and starting cylinders arranged between the several pairs of working cylinders.

3. In an internal combustion engine, pairs of working cylinders, each pair comprising a cylinder for the compression of a combustible gas and a cylinder for the compression of a burning gas, pistons acting in the said cylinders, a crank-shaft, connecting rods between the said crank shaftand the pistons, the said pistons reaching simultaneously the end of their compression stroke, whereby the combustible gas and the burning gas are compressed. simultaneously but separately from each other to the temperature of spontaneous ignition when mixed together a passage between both cylinders of each pair, a valve arranged in the said passage, means for actuating said valve, whereby the mixture of the combustible gas and of the burning gas is formed andspontaneously ignited when the corresponding pistons are at the end of their compression stroke, means for sup lying the combustible gas to the correspon ing cylinders under an initial pressure, exhaust valves cooperating with each cylinder of the several pairs of cylinders for the escape of the burnt gases two starting cylinders arranged between the several pairs of working cylinders, a piston in each of the said starting cylinders, the said pistons cooperating with the crank shaft of the working cylinders, whereby one of the starting pistons is in the starting position when the pistons of the working cylinders are, at rest, in a balanced position.

4. An internal combustion engine, including a plurality of pairs of working cylinders, each pair including independent compression chambers for ex losive and burning gases, means for independently initially compressing and supplying gases to'the corre sponding cylinders, pistons within said cylinders, connecting rods attached to said pistons, a crank-shaft, the pistons of each pair of cylinders being secured to said crankshaft in the same position relatively to the cylinders, passageways connecting the cylinders of each pair, a valve in each passageway adapted to maintain each. cylinder of a pair in independent relationship throughout the compression stroke, means for actuating said valve to establish communication between the cylinders of each pair adapted solely to cause spontaneous combustion of the gases and starting cylinders and pistons adapted to move the pistons in the working cylinders when said Working cylinders are in a state of equilibrium.

In testimony whereof signature.

JULES HECTOR DE GRAER.

I have affixed my 

